1st Gen Dakota Tech 1987 - 1996 Dodge Dakota Tech - The ultimate forum for technical help on the 1st Gen Dakota.

2.5 to a 3.9 swap

Thread Tools
 
Search this Thread
 
  #1  
Old 06-15-2012, 02:25 AM
John4649's Avatar
John4649
John4649 is offline
Rookie
Thread Starter
Join Date: Jun 2012
Location: Jacksonville fl
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default 2.5 to a 3.9 swap

I have a 1996 dakota With the 2.5l and would like to do a 3.9 v6 swap what all will I need and can I re use my 2.5 tranny if possible Oh and the v6 won't have ac in it
 
  #2  
Old 06-15-2012, 02:30 AM
Crazy4x4RT's Avatar
Crazy4x4RT
Crazy4x4RT is offline
Hall Of Fame
Join Date: Aug 2007
Location: NM
Posts: 10,926
Received 16 Likes on 15 Posts
Default

With the 96 it may be more intense versus 92-95 truck/engines as far as wiring and electronics. As far as bolting in, the few who have done engine swaps from the 4cly say it bolts right in. Yes the transmission will be fine for the V6 but if it is an auto it would be controlled by the PCM which you would need a 96 Dakota V6 PCM and wiring to make it all work.

Best way would be to get a complete donor truck and take what you need. If your doing the swap for more power you might as well do a V8 swap, 5.2 or 5.9 for the most bang for you buck.
 
  #3  
Old 06-15-2012, 02:40 AM
John4649's Avatar
John4649
John4649 is offline
Rookie
Thread Starter
Join Date: Jun 2012
Location: Jacksonville fl
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default

Dont want a v8 if I was going for the most power I would do a Nissan skyline rb26dett in the truck you can get a compete RB swap for 2000$ it has better specs than the 360 or 318 it's a street truck only I have atv for offroad after the swap I'm doing a 2in drop or a custom air bag setup
 
  #4  
Old 06-15-2012, 02:41 AM
John4649's Avatar
John4649
John4649 is offline
Rookie
Thread Starter
Join Date: Jun 2012
Location: Jacksonville fl
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default

Also my tranny is a 5 sped man
 
  #5  
Old 06-15-2012, 03:03 AM
John4649's Avatar
John4649
John4649 is offline
Rookie
Thread Starter
Join Date: Jun 2012
Location: Jacksonville fl
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default

Can I used my old wiring harnes from the 2.5 and the ecu I could use a list of things needed if any one has one
 
  #6  
Old 06-15-2012, 09:28 AM
volaredon's Avatar
volaredon
volaredon is offline
Record Breaker
Join Date: Apr 2010
Posts: 1,721
Received 48 Likes on 47 Posts
Default

Originally Posted by John4649
Also my tranny is a 5 sped man
youd need the bellhousing from a 6 cyl the rest of the tranny is the same.
 
The following users liked this post:
Goofy1 (02-19-2024)
  #7  
Old 02-19-2024, 07:58 AM
Goofy1's Avatar
Goofy1
Goofy1 is offline
Registered User
Join Date: Feb 2024
Posts: 2
Received 0 Likes on 0 Posts
Default 2.5 swap to V6 or V8

I have the 1995 Dakota Sport with a 2.5 motor and 5 speed standard transmission. Can I just pull the 2.5 standard bell housing off and bolt on the Standard V6 or V8 bell housing?
Are both the V6 and V8 bell housing the same bolt pattern?
The 4.7 V6 bolts right in? But the V8 needs motor mounts moved to bolt in my 95 Dakota Sport???
As long as both motors have throttle body carburetor the 95 Dakota's computer and wires will work, right???
 
  #8  
Old 02-19-2024, 08:21 AM
Goofy1's Avatar
Goofy1
Goofy1 is offline
Registered User
Join Date: Feb 2024
Posts: 2
Received 0 Likes on 0 Posts
Default 2.5 swap to V6 or V8

I have the 1995 Dakota Sport with a 2.5 motor and 5 speed standard transmission. Can I just pull the 2.5 standard bell housing off and bolt on the Standard V6 or V8 bell housing?
Are both the V6 and V8 bell housing the same bolt pattern?
The 4.7 V6 bolts right in? But the V8 needs motor mounts moved to bolt in my 95 Dakota Sport???
As long as both motors have throttle body carburetor the 95 Dakota's computer and wires will work, right???
 
  #9  
Old 02-21-2024, 10:58 AM
89sportboi's Avatar
89sportboi
89sportboi is offline
Registered User
Join Date: Feb 2024
Posts: 18
Likes: 0
Received 2 Likes on 2 Posts
Default

Originally Posted by John4649
Can I used my old wiring harnes from the 2.5 and the ecu I could use a list of things needed if any one has one
No, the harness for the 2.5 is significantly different/ different enough that unless you wanted to splice and rewire a significant portion of it you should just go ahead and find one at a junkyard. The ECU is also different and as far as I know not reprogrammable. as for a list I don't know if there is a complete one, you can look in the FAQ section but for starters:

3.9 v6 ECU and wiring harness
Complete engine and accessories
3.9 bellhousing
Fuel pump(? I've seen conflicting info if the fuel pump is the same or not)
engine mounts(even if you can reuse yours, you should replace)
radiator is different from looking at pics as well

Theres prob another 100 little bits and bobs that you may need as well but those should be most of the big components
 



Quick Reply: 2.5 to a 3.9 swap



All times are GMT -4. The time now is 10:41 AM.